/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.facebook.presto.iceberg.util;

/**
 * strategies that define how to merge hive column statistics into Iceberg column statistics.
 */
public enum HiveStatisticsMergeStrategy
{
    /**
     * Do not merge statistics from Hive
     */
    NONE,
    /**
     * Only merge NDV statistics from hive
     */
    USE_NDV,
    /**
     * Only merge null fractions from hive
     */
    USE_NULLS_FRACTIONS,
    /**
     * Merge both null fractions and NDVs from Hive
     */
    USE_NULLS_FRACTION_AND_NDV,
}
